Field of the Disclosure
The present disclosure is directed toward a toolbar hinge for an agricultural implement.
Description of the Related Art
The continued need to improve upon the prior art in the field of agricultural implements has resulted in the introduction of a number of folding toolbars, able to be placed in multiple positions to accommodate both operational and transportation requirements.
The art continues to be developed with the aim of improving capabilities of the implements while operating in the field optimizing stability of the implements when in a working position and in a transport position.
Many agricultural implements require lockdown pins to prevent or reduce unintended motion of articulating toolbars as the agricultural implements traverse uneven surfaces or hard to penetrate soils. The positioning of the toolbar on the back of the tractor places a heavy load on the tractor, leading to non-ideal circumstances such as instability, too much rear weight bias, and ultimately reducing the maximum payload the tractor can handle.
Further, conventional embodiments of agricultural implements are not optimal. Despite the need to occupy minimal space during storage, maneuvering, and transit, agricultural implements have relatively large widths in transport positions as a proportion of their dimensions when in working positions during operation. A smaller implement may be required to meet transport or machine storage limitations than required to match the tractor horsepower for field work. The increase in the number of passes needed to work an area directly results in greater fuel, time, and labor requirements than necessary.
FIG. 1A is a perspective view of a conventional embodiment of an agricultural implement 1 including a base toolbar 2, a first articulating toolbar 4a, a second articulating toolbar 4b, a first hinge 6a, a second hinge 6b, lockdown pins 8a and 8b, and three sets of row units 10a, 10b, and 10c, each including a plurality of row units 20 for strip tilling a ground surface. This embodiment illustrates strip till row units mounted to the toolbars. Other attachments may be used. The agricultural implement 1 is shown in a first position with the first articulating toolbar 4a and the second articulating toolbar 4b extended outwardly, substantially parallel to the ground (x-z) plane with the base toolbar 2 having a first end connected to the first hinge 6a and having a second end connected to the second hinge 6b. The base toolbar 2, the first articulating toolbar 4a, and the second articulating toolbar 4b are each connected to a set of row units 10a, 10b, and 10c, respectively. The first articulating toolbar 4a and the second articulating toolbar 4b are connected to the first hinge 6a and the second hinge 6b, respectively.
FIG. 1B and FIG. 1C are close-up perspective views of the connection between the base toolbar 2 and the first articulating toolbar 4a by the first hinge 6a, the first hinge 6a including a lockdown pin 8a. FIG. 1B illustrates the direction of insertion of the lockdown pin 8a into the first hinge 6a. FIG. 1C shows the lockdown pin 8a inserted into the first hinge 6a, preventing rotation of the hinge 6a and preventing the position of the first articulating toolbar 4a from changing relative to that of the base toolbar 2.
FIG. 2A is a perspective view of the conventional embodiment of the agricultural implement 1 including the base toolbar 2, the first articulating toolbar 4a, the second articulating toolbar 4b, the first hinge 6a, the second hinge 6b, and the three sets of row units 10a, 10b, and 10c. The agricultural implement 1 is shown in a second position with the first articulating toolbar 4a and the second articulating toolbar 4b folded, the base toolbar 2 having a first end connected to the first hinge 6a and having a second end connected to the second hinge 6b. The first articulating toolbar 4a articulates about the first end of the base toolbar 2 as both the first articulating toolbar 4a and the base toolbar 2 are connected by the first hinge 6a, and the second articulating toolbar 4b articulates about the second end of the base toolbar 2 as both the second articulating toolbar 4b and the base toolbar 2 are connected by the second hinge 6b. The rotation of the first hinge 6a and the second hinge 6b occur substantially about the x-axis. The ranges of motion of the first articulating toolbar 4a and the second articulating toolbar 4b about the first hinge 6a and the second hinge 6b, respectively, are limited due to the placement of the sets of the row units 10a, 10b, and 10c on the base toolbar 2, the first articulating toolbar 4a, and the second articulating toolbar 4b, respectively.
As the first articulating toolbar 4a articulates about the first hinge 6a from the first (extended, working) position of the agricultural implement 1 to the second (folded, transport) position of the agricultural implement 1 (folded), the set of row units 10a, specifically a row unit 20a, connected to the base toolbar 2 and the set of row units 10b, specifically a row unit 20b, connected to the first articulating toolbar 4a come into contact, limiting articulation of the first articulating toolbar 4a about the base toolbar 2.
As the second articulating toolbar 4b articulates about the second hinge 6b from the first position of the agricultural implement 1 (extended) to the second position of the agricultural implement 1 (folded), the set of the row units 10a connected to the base toolbar 2 and the set of the row units 10c connected to the second articulating toolbar 4b come into contact, limiting articulation of the second articulating toolbar 4b about the base toolbar 2.
FIG. 2B is a front view of the conventional embodiment of the agricultural implement 1 including the base toolbar 2, the first articulating toolbar 4a, the second articulating toolbar 4b, the first hinge 6a, the second hinge 6b, and the three sets of row units 10a, 10b, and 10c, each having a plurality of the row units 20. The agricultural implement 1 is shown in the y-z plane in a second position with the first articulating toolbar 4a and the second articulating toolbar 4b folded, the base toolbar 2 having a first end connected to the first hinge 6a and a second end connected to the second hinge 6b. The base toolbar 2, the first articulating toolbar 4a, and the second articulating toolbar 4b are connected to the sets of row units 10a, 10b, and 10c, respectively. The first articulating toolbar 4a articulates substantially in the y-z plane about the base toolbar 2 as both the first articulating toolbar 4a and the base toolbar 2 are connected by the first hinge 6a. The second articulating toolbar 4b articulates substantially in the y-z plane about the second end of the base toolbar 2 as both the second articulating toolbar 4b and the base toolbar 2 are connected by the second hinge 6b. 
As the first articulating toolbar 4a articulates about the first hinge 6a, contact between the set of the row units 10b of the first articulating toolbar 4a and the set of the row units 10a of the base toolbar 2, as provided in the description of FIG. 2A, prevents further articulation and limits the range of rotation of the first hinge 6a, forming angle α1 of about 55 degrees with the horizontal.
As the second articulating toolbar 4b articulates about the second hinge 6b, contact between the set of the row units 10c of the second articulating toolbar 4b and the set of the row units 10a of the base toolbar 2, as provided in the description of FIG. 2A, prevents further articulation and limits the range of rotation of the second hinge 6b, forming angle α2 of about 55 degrees with the horizontal.
FIG. 2C is a side view of the conventional embodiment of the agricultural implement 1 including the base toolbar 2, the first articulating toolbar 4a, the first hinge 6a, and the sets of the row units 10a and 10b. The agricultural implement 1 is shown in the x-y plane in a second position with the first articulating toolbar 4a folded and connected to the first hinge 6a, the base toolbar 2 having a first end connected to the first hinge 6a. The base toolbar 2 and the first articulating toolbar 4a are connected to the sets of row units 10a and 10b, respectively. The first articulating toolbar 4a articulates about the first end of the base toolbar 2 as both the first articulating toolbar 4a and the base toolbar 2 are connected by the first hinge 6a, with the first hinge 6a rotating substantially about the x-axis, in this embodiment forming a tilt angle β with the horizontal of approximately zero degrees.
As the first articulating toolbar 4a articulates about the first hinge 6a, contact between the set of row units 10b of the first articulating toolbar 4a and the set of the row units 10a of the base toolbar 2, as provided in the description of FIG. 2A, prevents further articulation and limits the range of rotation of the first hinge 6a. Because tilt angle β is zero in this embodiment, the first articulating toolbar 4a moves substantially in the y-z plane as it articulates, the position of the center of gravity (CG) of the agricultural implement 1 along the x-axis remains stationary and does not vary with articulation of the first articulating toolbar 4a. 
FIG. 2D is a side view of the conventional embodiment of the agricultural implement 1, shown in the x-y plane in the second (transport) position described by FIG. 2C, and connected to the rear of a tractor 26. The tractor 26 has a wheelbase A spanning the distance between the centers of a front wheel 22 and a rear wheel 24, while the distance B represents the distance from the center of the rear wheel 24 to the CG of the agricultural implement 1 in the transport position.
The combined mass of the tractor 26 and the mass of the agricultural implement 1 are supported by the front wheels 22 and the rear wheels 24. The location of the CG of the tractor 26 is generally within the wheelbase A while the CG of the agricultural implement 1 is behind the centerline of the rear wheel since all of the agricultural implement 1 is connected to and supported at the back of the tractor 26, behind the center of the rear wheel 24. The combined CG of the tractor 26 and the agricultural implement 1 is generally still located within the wheelbase A of the tractor 26, but closer to the rear of the tractor 26 than the CG of just the tractor 26 itself.
FIG. 2E is a front view of the conventional embodiment of the agricultural implement 1 connected to the tractor 26. The agricultural implement 1 is shown in an extended (working) position, with similar components to that described by FIG. 2B, including the base toolbar 2, the first articulating toolbar 4a, the second articulating toolbar 4b, the first hinge 6a, the second hinge 6b, and the three sets of row units 10a, 10b, and 10c, each having a plurality of the row units 20 that contact the ground surface. The agricultural implement 1 exerts a draft load on the tractor 26, draft load defined as the force needed to pull the implement parallel to the direction of travel.
By themselves the first articulating toolbar 4a and the second articulating toolbar 4b, and the set of row units 10b and 10c of the agricultural implement 1 have an undesirable tendency to rise up particularly as the row unit 20 furthest from the first and second hinges 6a and 6b, respectively, encounter hard or slightly uneven ground surfaces during operation behind the tractor 26 due to insufficient downward force acting upon them (e.g. the row unit 20n is not even with the row unit 20p), requiring the use of a lockdown pin 8a and lockdown pin 8b to ensure the toolbars 4a and 4b remain in the necessary extended position, and the sets of row units 10b and 10c connected to the toolbars 4a and 4b remain in contact with a ground surface.